vmscan: zone_reclaim() don't use insane swap_cluster_max

In old days, we didn't have sc.nr_to_reclaim and it brought
sc.swap_cluster_max misuse.

huge sc.swap_cluster_max might makes unnecessary OOM risk and no
performance benefit.

Now, we can stop its insane thing.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 63bd521..d55d106 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2539,8 +2539,7 @@ static int __zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
                .may_writepage = !!(zone_reclaim_mode & RECLAIM_WRITE),
                .may_unmap = !!(zone_reclaim_mode & RECLAIM_SWAP),
                .may_swap = 1,
-               .swap_cluster_max = max_t(unsigned long, nr_pages,
-                                      SWAP_CLUSTER_MAX),
+               .swap_cluster_max = SWAP_CLUSTER_MAX,
                .nr_to_reclaim = max_t(unsigned long, nr_pages,
                                       SWAP_CLUSTER_MAX),
                .gfp_mask = gfp_mask,